South Korean prosecutors are set to file an additional charge early this month against former President Park Geun-hye, who is standing trial on multiple charges, including bribery and abuse of power.

Former President Park Geun-hye. Yonhap

The ousted leader faces a new allegation that she received bribes from the National Intelligence Service while in office. Park has been detained at a correctional facility since she was arrested on March 31 and indicted on April 17 last year.

Prosecutors suspect that Park received part of the agency’s “special activities” budget between May 2013 and July 2016. The fund is intended to finance the most covert operations, and is not subject to audit or scrutiny by the National Assembly.

All three former NIS chiefs who worked under Park -- two of whom have been arrested and indicted -- face the allegation that they illegally channeled a total of 4 billion won ($3.6 million) to Park’s former presidential secretaries from the agency’s secret account. The former presidential secretaries are suspected of having transferred that money to Park.

The money might have been raised for a slush fund for Park, prosecutors suspect.

Park is expected to be indicted on the latest charge without further questioning as she refuses questioning in prison.